Merge pull request marshallpierce#167 from marshallpierce/mp/expose-encoded-len

Expose encoded_len function

Author: marshallpierce

RELEASE-NOTES.md

@@ -8,6 +8,7 @@
 - Since there are already multiple breaking changes, various functions are renamed to be more consistent and discoverable.
 - MSRV is now 1.47.0 to allow various things to use `const fn`.
 - `DecoderReader` now owns its inner reader, and can expose it via `into_inner()`. For symmetry, `EncoderWriter` can do the same with its writer.
+- `encoded_len` is now public so you can size encode buffers precisely.
 
 # 0.13.0
 

src/encode.rs

@@ -191,7 +191,10 @@ fn encode_with_padding<E: Engine>(
     debug_assert_eq!(expected_encoded_size, encoded_bytes);
 }
 
-/// calculate the base64 encoded string size, including padding if appropriate
+/// Calculate the base64 encoded length for a given input length, optionally including any
+/// appropriate padding bytes.
+///
+/// Returns `None` if the encoded length can't be represented in `usize`.
 pub fn encoded_len(bytes_len: usize, padding: bool) -> Option<usize> {
     let rem = bytes_len % 3;
 

src/lib.rs

@@ -109,9 +109,9 @@ pub mod engine;
 pub mod alphabet;
 
 mod encode;
-pub use crate::encode::encode_engine_slice;
 #[cfg(any(feature = "alloc", feature = "std", test))]
 pub use crate::encode::{encode, encode_engine, encode_engine_string};
+pub use crate::encode::{encode_engine_slice, encoded_len};
 
 mod decode;
 #[cfg(any(feature = "alloc", feature = "std", test))]